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Kickbutt's Science Notebook

As you all have no doubt seen, I've been writing one post per day on a kitchen experiment. I just thought, for reference, it would be easier to have in one location. I'll just add a new experiment each day in the replies. Keep on learning!

Ok, I admit it, I'm addicted to science. I would happily throw away all other subjects and just devote my kids learning to that one, if it were possible. Lol! As many of you know, I used to be an aeronautical/electrical engineer. I hold degrees in Physics & Geology. In this post I'll be posting my favorite science experiments. They most often include products found around your house (no fancy equipment needed!)

Each of my kids has a Science Journal. In it they write out every experiment, hypothesis and result. I have them format it the way many colleges require for Lab classes. The journal is one of those bound notebooks.

Format:

Experiment title

Supplies: a billeted list of all supplies, with exact measurements and weights

Process: a numbered list of the step by step process used, plus any variations

Hypothesis: what the kids think might happen as a result of the experiment

Conclusion: what the final result of the experiment was, did it match their hypotheses - why or why not. This also includes a paragraph or so explanation of what happened.

Voila. Science is complete! We don't stick to a specific form of science usually, we tend to mix things us. But we do an experiment just about every day.

Sometimes it’s hard to tell SCIENCE from MAGIC - and this little demonstration is a great example of that. In this experiment you will watch an almost clear liquid suddenly turn dark blue in a flash. It takes a bit of preparation, and probably a trip to the pharmacy for materials, but we think it’s worth it.

IMPORTANT SAFETY INFORMATION: This experiment should only be done with the help of an adult. Iodine will stain just about anything it touches and it can be hazardous. Hydrogen peroxide can cause eye and skin irritation - safety goggles are needed throughout the experiment. Be sure your helpful adult reads the caution labels on each container.

3 clear plastic cups 4 ounces or larger

A 1000 mg Vitamin C tablet from the pharmacy (you can also use two 500mg)

Tincture of iodine (2%) also from the pharmacy

Hydrogen peroxide (3%) yep, also from the pharmacy

Liquid laundry starch (see below for alternatives)

Safety goggles

Measuring spoons

Measuring cup

An adult helper

Put on those safety goggles and mash the 1000 mg Vitamin C tablet by placing it into a plastic bag and crushing it with a rolling pin or the back of a large spoon. Get it into as much of a fine powder as possible. Then put all the powder in the first cup and add 2 ounces (60 ml) of warm water. Stir for at least 30 seconds. (The water may be a little cloudy) Let’s call this “LIQUID A”

Now put 1 teaspoon (5 ml) of your LIQUID A into a new cup and add to it: 2 oz (60 ml) of warm water and 1 teaspoon (5 ml) of the iodine. Notice the brown iodine turned clear! Let’s call this “LIQUID B.” By the way, you’re done with LIQUID A - you can put it aside.

In the last cup, mix 2 oz of warm water, 1 Tablespoon (15 ml) of the hydrogen peroxide and 1/2 teaspoon (2.5 ml) of the liquid starch. This is, you guessed it, “LIQUID C”

Okay, that was a lot of preparation, on to the fun part. Gather the friends and family and pour all of LIQUID B into LIQUID C. Then pour them back and fourth between the 2 cups a few times. Place the cup down and observe….be patient....somewhere between a few seconds and a few minutes, the liquid will suddenly turn dark blue!

This is an example of the chemical reaction know as the IODINECLOCK REACTION. It is called a clock reaction because you can change the amount if time it takes for the liquids to turn blue. (see experiments below) The chemistry of the demonstration gets a bit complicated, but basically it is a battle of chemistry between the starch which is trying to turn the iodine blue, and the Vitamin C which is keeping it from turning blue. Eventually the Vitamin C loses and, bam! - you get instant blueness.

Note: If you do not have liquid starch, you can also use 1/2 teaspoon of corn starch or potato starch. The liquids will be more cloudy and the reaction will happen a bit more slowly, but it’s still impressive.

Clean up: Carefully pour all liquids down the drain with plenty of water and wash your hands. Recycle the cups or dispose of them in the trash.

The project above is a DEMONSTRATION. To make it a true experiment, you can try to answer these questions:

1. Does the temperature of the water affect how quickly the liquids turn blue?2. Does the amount of Vitamin C added (Liquid A) affect how fast the liquid turns blue?3. Does stirring the liquids more affect how fast the liquids turn blue?

Remove any labels from the bottle and fill it all the way to the top with water.

Add a ketchup pack to the bottle.

If the ketchup floats, you're all set - go to step 4. If the ketchup sinks in the bottle, go to step 5.

For the floating ketchup pack simply screw the cap on the bottle and squeeze the sides of the bottle hard. If the ketchup sinks when you squeeze it, and floats when you release it, congratulations, you're ready to show it off. If it does not sink when you squeeze it, try a different kind of ketchup pack or try a mustard or soy sauce pack.

If the ketchup pack sinks, add about 3 tablespoons (45 ml) of salt to the bottle. Cap it and shake it up until the salt dissolves. (Kosher salt will keep the water from getting too cloudy, although it will usually clear up over time if using regular table salt.)

Continue adding salt, a few tablespoons at a time until the ketchup is just barely floating to the top of the bottle.

Once it is consistently floating, make sure the bottle is filled to the top with water, and then cap it tightly.

Now squeeze the bottle. The magic ketchup should sink when you squeeze the bottle and float up when you release it. With some practice you can get it to stop in the middle of the bottle.

This experiment is all about buoyancy and density. Buoyancy describes whether objects float or sink. This usually describes how things float in liquids, but it can also describe how things float or sink in and various gasses.

Density deals with the amount of mass an object has. Adding salt to the water adjusted the water's density to get the ketchup to float. Sound complicated? It is, but here's the basics on the ketchup demo...there is a little bubble inside of the ketchup packet. As we know bubbles float, and the bubble in the ketchup sometimes keeps the heavy packet from sinking. When you squeeze the bottle hard enough, you put pressure on the packet. That causes the bubble to get smaller and the entire packet to become MORE DENSE than the water around it and the packet sinks. When you release the pressure, the bubble expands, making the packet less dense (and more buoyant) and, alas, it floats back up. This demonstration is sometimes known as a CARTESIAN DIVER.

The project above is a DEMONSTRATION. To make it a true experiment, you can try to answer these questions:

1. Do different food packs (ketchup, mustard, soy sauce) have the same density?

2. Does the temperature of the water affect the density of the ketchup packet?

3. Does the size of the bottle affect how much you have to squeeze to get the packet to sink?

A film canister, baby food jar, or other similar size container with an mouth slightly larger than a penny

Pencil or pen

Scissors

Cut the cardstock paper into a long strip about .75 inches (2 cm) wide and form it into a hoop as shown. The paper should be stiff enough to hold the hoop shape on its own and the hoop works best when it is between 3-4 inches (8-10 cm) across.

For dramatic effect, fill the film canister with water and place on a level surface.

Place the hoop on the film canister as shown and balance the penny on the top of the hoop.

Time for Lincoln's big moment! Place a pencil through the center of the hoop and in one swift motion fling the hoop off to the side as pictured. If you do this correctly, the hoop will fly out of the way, and the penny will fall straight down into the canister with a splash. 10 points for Lincoln!

THE SETUP

THE DIVE

This is science? You betcha. Part of Newton's first laws says, in general, that an object at rest will remain at rest unless acted upon by an outside force. The energy of your movement with the pencil was passed on to the hoop, making it fly out of the way quickly, but the hoop moved too fast, and there was not enough friction to affect the penny (at rest) on top of the hoop. The penny ended up above the film canister with nothing to hold it up. It was about then that gravity took over, and pulled the coin straight down into the waiting water. Yep, Issac Newton and Abraham Lincoln, together in the name of science...sort of.

The project above is a DEMONSTRATION. To make it a true experiment, you can try to answer these questions:

1. Does the size of the hoop affect the accuracy of the falling coin?2. Does the shape of the object on the hoop affect the accuracy of the drop?3. Is the coin affected by how fast you fling the hoop out of the way.

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